This invention relates to antennas and more particularly to a foldable log-periodic antenna.
The use of communications and other electronic equipment in the field often requires the positioning of a log-perodic antenna at heights of 18 feet or more above the ground in order to prevent ground interference with signals being radiated or received by the antenna. In the case of portable tactical military systems it is essential that such an antenna be elevated from a stowed position on the transporting vehicle to the operative position quickly and with a minimum of personnel, ideally one person. In addition, the antenna and its support in the stowed position on the vehicle should be sufficiently compact as to not interfere with mobility of the vehicle in the field or on heavily trafficked roads.
An erectable log-periodic antenna system of the general type mentioned above has been built in the past but has several disadvantages. The antenna boom comprises three separate pieces. The 36 radiating elements are removably secured to the boom and are bundled together for stowing. The mast has several separate sections which are coupled together and the antenna is mounted on top of the mast after the latter has been raised to the vertical position. The disadvantages of this system are excessive assembly time, the large number of separate pieces and the complex assembly procedure leads to loss of parts and unreliability, difficulty of assembly especially in snow and mud, at least two operators are required to assemble and disassemble the system, and assembly of the system requires a large amount of open space around the supporting vehicle.
This invention is directed to an improved antenna that overcomes the above mentioned disadvantages.